Refactor authentication routes to use '/auth' prefix in API calls

backend/tests/test_child_override_api.py

@@ -46,7 +46,7 @@ def add_test_user():
 
 def login_and_set_cookie(client):
     """Login and set authentication cookie."""
-    resp = client.post('/login', json={
+    resp = client.post('/auth/login', json={
         "email": TEST_EMAIL,
         "password": TEST_PASSWORD
     })
@@ -59,7 +59,7 @@ def client():
     app = Flask(__name__)
     app.register_blueprint(child_override_api)
     app.register_blueprint(child_api)
-    app.register_blueprint(auth_api)
+    app.register_blueprint(auth_api, url_prefix='/auth')
     app.config['TESTING'] = True
     app.config['SECRET_KEY'] = 'supersecretkey'